1. Field of the Invention
This invention generally relates to bicycle shift operating device. More specifically, the present invention relates to a bicycle shift operating device with an increased cable stroke relative to the amount of actuation of the operating member.
2. Background Information
Bicycling is becoming an increasingly more popular form of recreation as well as a means of transportation. Moreover, bicycling has become a very popular competitive sport for both amateurs and professionals. Whether the bicycle is used for recreation, transportation or competition, the bicycle industry is constantly improving the various components of the bicycle. One component that has been extensively redesigned is the bicycle transmission system.
The bicycle transmission system typically includes front and rear shift operating devices that operate front and rear derailleurs to laterally shift a chain between front and rear sprockets, respectively. The front and rear sprockets are usually coupled to the front crank and the rear wheel, respectively, such that the pedaling force from the rider is transferred to the rear wheel via the chain. Depending on the position of the chain on the front and rear sprockets, a variety of gear ratios can be provided.
In the past, shift operating devices have been utilized that include one or more levers that are pivoted in order to wind and unwind an inner wire of a control cable. Alternatively, rotating hand grips have also been utilized as shift operating devices to wind and unwind the inner wire of the control cable. Two shift operating devices are typically provided on multi-speed bicycles. Typically, one shift operating devices is a front shifting mechanism, while the other shift operating devices is a rear shifting mechanism. Each shift operating device is usually connected to an inner wire of a control cable. The inner wires of the control cables extend from the front and rear one shift operating devices to the front and rear derailleurs to shift the chain over the various front and rear sprockets, respectively. Typically, a takeup wheel or member is used to wind and unwind the inner wire about its peripheral edge. Some derailleturs require a longer cable stroke than other derailleurs. Thus, as the cable stroke of the derailleur becomes longer, then the takeup wheel becomes larger. While these prior shifting devices work well, it is desirable to make the bicycle shift operating devices relatively compact as possible. However, when the cable take up unit becomes smaller, then the amount that the operating member of the shift operating device must be moved becomes larger for the same transmission system. In other words, if the cable take up unit becomes small, then the stroke of the operating member becomes larger making it more difficult to operate.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved bicycle shift operating device. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.